Physical quantity measuring devices include: a pressure transmitter including a detector that detects a physical quantity; and a circuit board that receives the detection signal from the detector and outputs a signal to an external device.
A typical example of the pressure transmitter is a pressure sensor including a housing, a pressure transducer housed in the housing, an electric circuit, and a connector terminal, the pressure transducer outputting a signal to an external device through the electric circuit and the connector terminal (see Patent Literature 1: Japanese Utility Model Registration No. 2540967).
In the typical device of Patent Literature 1, the connector terminal is provided to a connector body, and an electronic circuit board provided with the electric circuit is disposed in a space defined by the connector body and the housing. A trimmer or the like is adjusted by operating a variable resistor, which is provided to the electric circuit, with a tool such as a driver. The connector body includes a cylindrical portion covering the connector terminal, the cylindrical portion being provided therein with a plurality of adjustment holes required for the operation with the driver. The adjustment holes are each closed with a rubber stopper and sealed with a sealing material.
Another typical example of the pressure transmitter is a pressure detector including: a base; an upper cover; a circuit board disposed in a space defined between the base and the upper cover; and a pressure detector provided to the circuit board, the pressure detector outputting a detection signal to an external device through the circuit board and a lead wire (see Patent Literature 2: JP-A-11-118647).
In the typical device of Patent Literature 2, the circuit board is provided with a trimmer for adjusting a preset pressure of the pressure detector, the trimmer being operable when a trimmer cover provided to the upper cover is removed. One side of the trimmer cover is rotatably attached to the upper cover with a rotation shaft.
In the typical device of Patent Literature 1, when the electric circuit is adjusted, the adjustment holes are each closed with the rubber stopper and then sealed. Thus, once the adjustment holes are each closed by the rubber stopper, the electric circuit cannot be adjusted again. Even if the rubber stopper is removed, the driver cannot be inserted into the adjustment holes provided in the cylindrical portion, after the tip end of the connector terminal is connected to a connection member.
Therefore, in the typical device of Patent Literature 1, after device assembly is completed, it is difficult to adjust the electric circuit.
In the typical device of Patent Literature 2, since the trimmer cover is rotatably attached to the upper cover with the rotation shaft, the trimmer is adjustable when the trimmer cover is removed even after device assembly is completed.
However, the typical device of Patent Literature 2 employs a complicated arrangement where the trimmer cover is attached to the upper cover with the rotation shaft, which results in high production costs of the device.